Process and apparatus for the reproduction and recording of sounds



G. CHAMPION Filed July 24, 1933 Nov. 3, 1936.

PROCESS AND APPARATUS FOR THE REPRODUCTION AND RECORDING OF SOUNDS Patented Nov. 3, 1936 UNITED STATES PATENT OFFICE PROCESS AND APPARATUS FOR THE REPRODUCTION AND RECORDING OF SOUNDS Claims.

This invention relates to improvements in apparatus for the reproduction and recording of sounds, characterized by the fact that in reproducing or recording the sounds, the device for 5 analyzing the sound record or the device for recording the sounds is the one that travels rapidly over the sound track or the material to be impressed, as the case may be.

The following are the main features of the apparatus used for the reproduction of the sounds:

(a) The use of a plurality of photoelectric pick-ups, instead of one, and which are so arranged that, on being set in motion, they operate alternatively, to obtain thus the continuity of the sound, on travelling over and analyzing the sound lines or tracks of the sound record or ribbon.

(b) In this sound reproducing apparatus, the photoelectric pick-ups travel over rapidly and analyze the sound tracks of the record, instead of the sound record displacing rapidly in front of a photoelectric pick-up which is fixed, as usual heretofore in apparatus of this kind.

(c) During the sound reproduction, the photoelectric pick-ups move rapidly and travel over the sound record transversely thereof, while the sound record moves slowly.

(d) During the sound reproduction, the material on which the sounds are recorded, displaces at slow speed to continually present a new sound track to the corresponding pick-up.

The above features bring about the following advantages:

(a) It is possible to use sheets or bands with 5 the sound tracks arranged transversely and interrupted at their ends, the phonetical reproduction of which is obtained through the use of several photoelectric pick-ups so arranged that when one of the said pick-ups travels over and finishes analyzing one of the sound tracks, an-

other photoelectric pick-up starts travelling over the next sound track, thus obtaining the phonetical continuity of the sounds registered.

(b) By the use of bands or ribbons with the sound tracks printed transversely thereon, long musical programmes and conferences may be registered without interruptions, as said bands may be of any convenient width and of the length required by the amount of sounds to be recorded,

from a few centimetres to several metres.

(0) Because of the slow displacement of the material having the sounds printed thereon, the friction is insignificant and there is practically no wear of the material.

To indicate the great advantage presented by this apparatus, with regard to the duration reached by the sound reproduction in relation to the limited dimensions of the material having the sound tracks arranged transversely, as mentioned above, the following example is offered: The phonetical reproduction of a sound record sheet of 40x 50 centimetres, printed with sound tracks two millimetres wide, will last three and one half minutes, while a band 40 centimetres wide by ten metres long, will last one hour and ten minutes.

By way of example, and for the purpose of showing the invention materialized and in one of the many ways in which it can be carried into practice, the same is illustrated in the accompanying drawing, wherein the same reference numbers indicate corresponding parts throughout the different figures.

Figure 1 is a top detailed view of the apparatus, with a portion of the printed record material 24 with sound tracks 25, showing how the photoelectric pick-ups I are combined so that as soon as one of them finishes travelling over and analyzing a sound track 25, another photoelectric pick up I starts travelling over and analyzing the next corresponding track 25.

Figure 2 is a detailed front view of the same apparatus.

Figure 3 is a detailed, partly schematic side elevation of the said apparatus, on the line AB of Fig. 1, showing one of the many ways in which a sheet or band 24 having sound tracks 25, may be passed in front of the photoelectric pick-ups l, for the sound reproduction, to permit such compact construction that the apparatus is relatively small.

Fig. 4 is a detailed view of part of the apparatus shown in Fig. 3.

This apparatus comprises two main parts: one destined to move the photoelectric pick-ups I rapidly, and the other to adjust and slowly displace the ribbon or band 24 having the sound tracks 25.

In the embodiment of the invention here shown there is employed a plurality of photoelectric pick-ups I each comprising a photoelectric cell such as is usual and an optic-electric system constituted by luminous focus or source, a diaphragm and lenses to condense the light beams in a suitable manner. The photoelectric pick-up may also comprise only a photoelectric cell.

These pick-ups are arranged in a circle on the outer ends of arms 3 which radiate from a vertical shaft 3 which in practice is mounted in suitable bearings and is provided at its lower end with a mitre gear. A commutator 2 is fixedly mounted on said shafts and is composed of a plurality of electric conducting discs or disc segments which are insulated from one another and each of which is connected to a corresponding photoelectric pick-up I.

A horizontally arranged shaft I which in prac tice is mounted in suitable bearings is provided with a bevelled gear 6 which engages the gear 5 and is also provided with a pinion 3 and with a spur gear 9.

An electric motor is indicated at I4 and its shaft I3 is provided with a pinion I2 which engages a gear I0 which rotates freely on an axial shaft II, together with a pinion Io which pinion engages the gear 9 of the shaft 1 so that said shaft I which operates the photoelectric pick-ups is driven at a much lower rate of speed than that of the motor shaft. I v

The cylinder H which actuates the record ribbon 24 and is provided with the usual studs I8 for engagement in the usual slots 23 of the record ribbon has a shaft I6 which in practiceis mounted in suitable bearings and said shaft has a large gear wheel I5 which is engaged by the pinion 8 of the shaft 1 so that the said record feeding or driving cylinder 1 is rotated at a'much lower rate of speed than the shaft I, the various gears being so proportioned in diameter that the record ribbon will be fed a distance equal to the space between two of the transverse curved sound tracks 25 with which it is provided, as indicated especially in Figure 1 while one of the photoelectric pick-ups is moving transversely across the record ribbon and hence each photoelectric pickup enters one of such curved sound tracks while the immediately preceding pick-up leaves the next preceding sound track, as will be understood, so that the photoelectric pick-ups operate continuously and successively and are successively continuously engaged with the sound tracks, in succession, of the record ribbon.

A roller I9 which serves to maintain the tension of the record ribbon 24 in front of the photoelectric pick-ups to facilitate the phonetic reproduction of the sound tracks 25 bears against the under side of the record ribbon and 'its shaft is mounted in bearings provided in the down turned end portions of the convexly curved guide plate 20 under which the record ribbon passes. Said guide plate has a slot through which the upper portion of the periphery of the tension roller I9 passes so as to be in engagement with the under side of the record ribbon, and a roller 22 which bears on the upper side of the record ribbon has its shaft mounted in bearings in a pair of brackets 2I which are pivotally mounted on the downturned end portions of the guide plate as shown. Said rollers I9, 22 coact to impart the required tension to the record ribbon.

An electric amplifier is indicated at 26 and is electrically connected by suitable conducting wires to the brushes 4 which transmit electric current to the commutator 2 and which amplifier is also electrically connected by suitable conducting wires to the loud speaker 21.

This description corresponds to an apparatus using sound record tracks 25 impressed on opaque material 24, to operate by light reflection. In this case, the light beam falls on the sound track 25 and is reflected, affected by the luminous fluctuations which impress the photoelectric cell, transforming same into electric variations; these variations pass through the electric circuit of the reproducing apparatus 26 and. reach the loudspeaker 21, or telephones, whereupon they are converted into sounds.

In the case of the present apparatus, said photoelectric pick-ups are equidistantly mounted on a radial support fixed to a vertical shaft 3, with its corresponding commutator 2 which rotates with same; the electrical continuity between the photoelectric pick-ups I and the electric system of the reproducing apparatus 26 is established by means of the contact brushes 4.

2 is the commutator which is fixedly mounted on the shaft 3 and the mass of supports of the photoelectric pick-up I. This commutator is constituted by a plurality of electricity conducting discs or disc segments, mounted on the shaft 3, insulated from each other and connected to the corresponding photoelectric pick-ups I.

3 is the vertical shaft formed by a metallic bar which is fixed to the mass of radial supports of the photoelectric pick-ups I and the commutator 2, to give them rotary movement.

4 are the brushes which transmit the electric current to the commutator 2.

5 is the conical gear, which is fixed to the lower end of the shaft 3, to rotate the latter.

6 is the conical crown fixed to the shaft I which transmits movement to the gear 5.

I is the shaft having the conical crown 6 at one end, and the cylindrical gears 8 and 9 mounted on the other.

8 is the cylindrical gear fixed to the shaft I and by means of which, rotary movement is transmitted to the shaft I6 of the cylinder II through the gear I5.

9 is the cylindrical gear, fixedly mounted on the shaft 1, which receives rotary movement from the motor I4 by means of the gears I0 and I2.

I0 is the intermediary gear which rotates freely on the shaft II and transmits the movement of the command shaft' I3 to another cylindrical gear 9.

II is the shaft on which the intermediary gear II] rotates freely.

I2 is the gear fixed to the command shaft I3 which transmits movement to the apparatus by means of the intermediary gear I0.

I4 is the motor which transmits movement to the apparatus through the command shaft I3 and cylindrical gear I2.

I5 is the cylindrical gear which is fixed to the shaft I6 and which receives movement from the gear 8.

I6 is the shaft on the axle of which the cylinder I1 rotates.

I1 is the cylinder which serves to cause the displacement of the sheet or band 24 on which the sound tracks 25 are printed.

I3 are the pivots or teeth fixed to the cylinder IT, to be inserted in the orifices or grooves 23 of the printed material 24, in order to secure the necessary synchronism and adjustment of the tracks 25 with the photoelectric pick-ups I.

I9 is the roller which serves to maintain the tension of the sheet or band 24 in front of the photoelectric pick-ups I, to facilitate the phonetical reproduction of the sound tracks 25, both ends of said roller being fastened to the support 20 by means of a shaft.

20 is the support on which the material 24 is displaced. It is formed of sheet metal, slightly curved, fiat ended and arranged horizontally; on both sides it is turned downwardly, which provides a support for the shaft of the roller I9 and support 2|. An opening 20' is provided in front of the roller I9, which allows the material 24 to remain in contact with the orifices 22 and the roller l9.

2| are movable brackets or supports, which support the rollers 22 acting on the roller l9. These brackets are link connected to the support 20.

23 are the orifices or grooves practiced in the material 24 to actuate the material impressed and avoid its disadjustment, thus securing a perfect synchronism with the moving photoelectric pick-ups.

24 is the material on which thesound tracks 25 are impressed.

25 are the sound tracks printed or impressed on the material 24.

26 is the electric amplifier, and

21 is the loudspeaker.

For the sound reproduction, the band or printed material 24 is applied on the roller l9, fastened laterally with the rollers 22, passed over the flat portion of the support 20 and over the roller l1, engaging the pivots or teeth [8 of the main roller H, with the corresponding lateral orifices 23, so that the band 24 will be well extended over 20 and Il in the part remaining in front of the path of the photoelectric pick-ups, over the material 24.

The motor is started and, through the gear system hereinbefore described transmits rapid movement to the pick-ups l and a slow movement to the cylinder H. The synchronism is effected in such manner that when one pick-up finishes travelling over a sound track, the other pick-up starts travelling over the track that follows phonetically and which, in this case, is the one immediately below. The photoelectric cells thus energized, transmit electric fluctuations to the amplifying circuit 26 and on to the loudspeaker 21 which converts them into sounds.

When a pick-up leaves a sound track, the light beam, having nothing to reflect on, stops impressing the photoelectric cell and its travel out of the sound record is silent, while the other pick-up is travelling over the next sound track.

I would have it understood that the apparatus herein described as an example may be subject to numerous modifications. The one described employs three pick-ups, but same could be constructed to use two or more than three, mounted on one or more shafts or guides and with curved or straight movement or a combination of both, always in a transverse sense in relation to the displacement course of the sound record during the sound reproduction.

As regards the cylinder ll, same can also be modified. It could be provided with projections close together, on both edges, to engage sound records having lateral perforations similar to those carried by the usual cinematograph films, or, instead, they could carry small lateral metal plates applied on the sound records. It may carry magnets or electromagnets to attract the sound record having magnetic material. The adjustment of the record on the cylinder, may be effected by vacuum, or by rollers, or by means of depressions to take foldings on the sound record, or by any other suitable means.

The cylinder may also be replaced by an endless plate, on which the sound record would be fixed by any process, for example one of the methods described for the cylinder.

For the use of sound records in rolls, it will only be necessary to add a device to support said rolls and roll the bands.

If instead of using sound records printed on opaque material, transparent material is used, the mechanism of the apparatus will have to be modified by placing the optic-luminous system forming part of the photoelectric pick-up above described, underneath the sound record, while the photoelectric cell would remain on top, that is to say, that they would be separated by the sound record, and they are provided with the same synchronic movement. In this manner, the light beam issued by the optic system goes through the printed material and impresses the photoelectric cell directly. In this case, a screen should be placed in the path of the pick-up outside of the sound record, between the light beam and the photoelectric cell, so that the pick-ups will travel silently outside of the sound record zone. Said screen may be made of any suitable opaque material.

Also, instead of photoelectric cells, any other suitable device for analyzing the sound record tracks may be used.

In cases where this sound reproducing apparatus is used for the photoelectric recording of the sounds, the photoelectric pick-ups I will be substituted by oscillographs or vibrating lamps with corresponding optic-electric devices used in the photoelectric recording of the sounds, and instead of using the printed material 24, a photographically sensitized film or paper, or other substance sensitized to the luminous or other rays, is employed. Also, an electric circuit suitable for the photoelectric recording of sounds, with the corresponding microphone, should be provided.

Instead of oscillographs, any suitable sound recording device may be used.

All the modifications which it is possible to apply to the reproducing apparatus, can also be introduced to the record.

Having now particularly described and ascertained the nature and scope of the present invention and the manner in which same is carried into practice, I declare that what I claim is:

1. In apparatus of the class described, a record element having sound tracks extending transversely thereon and curved in the direction of the length thereof; a series of pick-ups each of which being equipped with a photoelectric cell and arranged to move in succession through the said sound tracks in a curve lying in a plane parallel to that of said record, electrical sound translating means continuously conductively connected with said pick-ups and actuating means for said record element and said series of pick-ups, the radius of each curved sound track of the record element being identical with that of the curved path of movement of the pick-ups and the actuating means for the record element and the series of pick-ups being of such speed as to cause each pick-up in succession to enter one of the sound tracks immediately after its predecessors moves out of the preceding sound track.

2. Apparatus as claimed in claim 1, in which the series of photoelectric pick-ups is mounted in a circle of substantially larger diameter than the width of said record element and for rotation in a plane parallel to that of the record element.

3. Apparatus of the class described, comprising multiple pick-ups each constituted by a system of lens concentrating the light issued by a, focus, and a photoelectric cell, mounted on a common axle having rotary movement; a phonogram; means to displace the phonogram slowly in synchronism with the displacement of the pick-ups which analyze the sound record tracks which are juxtaposed and transverse with respect to the displacement direction of the phonogram, and means for converting into sounds the electrical variations originated in the photoelectric cells, the path of movement of the pickups being in a plane parallel with and proximate to the opposed surface of the phonogram and the speed of movement of the pick-ups, the speed of movement of the phonogram and the width of the record tracks on the phonogram being of such relation that each pick-up enters a record track immediately after the preceding pick-up leaves the preceding track, so that the effect is continuous and not interrupted.

4. A phonogram for the apparatus claimed in claim 3, characterized in that it has a sound record trace arranged in the form of multiple curved juxtaposed tracks on a sheet of opaque material.

5. A phonogram for the apparatus claimed in claim 3, characterized in that it has a sound record trace arranged in the form of multiple curved juxtaposed tracks on a wide band of opaque material.

GASTON CHAMPION. 

